Radio receiving apparatus



Sept. 28, 1926. 1,601,619

A. HAGERMAN RADIO RECEIVING APPARATUS Filed June 2, 1924 5 ATTORNEY WITH 55:

Patented Sept. 28, 1926.

UNITED STATES PATENT OFFICE.

ARTHUR.HAGERMAN, OF VILAS, KANSAS.

RADIO RECEIVING APPARATUS.

Application filed June 2, 1924. Serial No. 717,376.

movable to vary the inductance for tuning purposes, the stationary coil also being of such construction that the inductance thereof may be controlled.

Yet another object is the provision of an apparatus of this character in which the stationary coil serves as a housing for the vacuum tube which is used as the detector, the tube being thereby protected against injury through careless handling.

An additional object is the provision of an apparatus of this character which will be simple and inexpensive in manufacture, easy to set up and use, also easy to control or tune, positive in action, efficient and durable in service and a general improvement in the art.

lVith the above and other objects and advantages in view the invention consistsin the details of construction tobe hereinafter more fully described and claimed and illustrated in the accompanying drawings, in which:

Figure 1 is a plan view of the complete device,

Figure 2 is a side elevation.

Referring more particularly to the drawings the numeral designates a base on which is mounted, by any suitable means, a triangular frame 11 on the top of which is mounted a cover plate 12 on which is pivoted a switch 13 including a control knob 14 and a switch arm 15 adapted to be brought into contact with anyone of a series of switch points 16. This frame 11 is wound with a coil of wire 14 which is tapped off at intervals, the taps being brought out and connected to the respective switch points 16. On the top of this cover plate 12 is an aerial binding post 17 represented in the diagram as connected with the switch arm 13. On the cover is also a binding post 18 intended for connection with the ground and one end of the coil 14 connects with this 55 binding post 18.

The cover plate 12 may be of hard rubber,

bakelite or other suitable dielectric material and is here shown as mounted on theframe by means of screws 19. The means for mounting this unit on the base may very conveniently be a rod 20 rising from the base and passing through the cover plate and carrying a clamping nut 21. It should of course be understood that these details may be varied to suit the preference of the maker.

Mounted on the base 10 within the confines of the frame 11 is a conventional vacuum tube socket 22 of any style preferred depending upon the type of tube to be used and the cover plate 12 is formed with an opening 23 which will permit insertion of the tube therethrough so that it may be engaged within the socket.

Mounted on the base at one side of the above described unit is a movable unit which consists of a triangular frame 24 having one corner engaged upon an upstanding pin 25 which rises from the base and which is formed with an enlarged bottom portion 26 having a threaded socket for receiving a securing screw 27 which is countersunk into the base. By this particular mounting it will be seen that the frame 24 may be swung so as to lie against the stationary unit or to be disposed at any desired distance therefrom. The top of the frame 24 is closed by a cover plate 27 held in place by screws 28 and carrying a knob 29 which may be grasped for adjusting the position of the movable unit.

The frame 24 is wound with a coil of wire 30 which constitutes the secondary coil of the coupler and the terminals of this coil are brought to binding posts 31 and 32 on the cover 27.

Mounted on the base 10 at some convenient point are binding posts 33, 34, 35, 36 and 37 designed for connection respectively with the positive terminal of the high voltage or plate battery, the negative terminal thereof, the positive terminal of the filament heating battery, the negative terminal thereof and the phones. Obviously the connections may be varied to suit the requirements of the individual owner or of the maker, depending upon the circuit contemplated.

As practically most hook ups require the use of a grid condenser and grid leak for the tube, I provide a conventional grid condenser which depends from the cover 12 and which is held by screws 39. Between the screws. 39 may be drawn a lead pencil mark 40 which constitutes the grid leak. The grid condenser and leak are interposed in the lead between the binding post 31 and the grid terminal of the tube.

In tuning the primary inductance is varied by moving the switch arm '15 over the switch points 16 until the proper one is found. The coupling between the primary and secondary is varied by grasping the knob 29 and varying the position of the pivoted secondary coil. Actual practice has demonstrated the apparatus to be highly eflicient in addition to the advantage ofbeing most compact.

\Yhile I have shown and described the preferred embodiment of my invention it is of course to he understood that I reserve the right to make such changes in the form, construction and'arrangement of partsas will not depart from the spirit of the invention or the scope of the subjoined claim.

I claim:

In a radio receiving apparatus, a variocoupler comprising a stationary frame of triangular shape carrying a tapped coil and serving as means upon which the terminal elements may be mounted, the coil constituting a primary, and a movable frame of triangular shape carrying a coil constituting a secondary, the second named frame being pivotally mounted near one corner adjacent a' corner of the stationary frame whereby the movable frame may be swung into a position in which one of its sides abuts throughout its length with a side of the stationary frame.

In testimony whereof I aflix my signature.

ARTHUR HAGERMAN 

